In this session 6 experts provide their research Energy Efficiency, Challenges, and Solutions. They include Joseph Rollin of Virginia Polytechnic Institute and State University, Ludovico Cademartiri of Harvard University, Alex Romriell of Brigham Young University, Fanxing Li of The Ohio State University, Danahe Marmolejo-Correa of the Norwegian University of Science and Technology, and Yasuki Kansha of the Institute of Industrial Science at The University of Tokyo.